When I was in middle school, I had friend who's family owned an inexpensive motel in downtown Reno. Yes, it was that glamorous. After playing basketball we'd go to his house and his mother would give us quarters that came from the slot machine in the motel office. We'd take the money and buy pizza then hang out in my friend's big brother's room. I'm sure everyone had a friend with a big brother who smoked pot, had an American flag hanging on the wall, needed a haircut or two, and loafed around all day. I should have been impressed by his coolness factor, but never really was. He was always too stoned, looked dirty, and his balls would fall out of his too short shorts when he passed out. But his room was covered with black light posters lit by an overhead black light. Seriously groovy.
The black light posters of the 1960s and 70s were printed with fluorescent inks and displayed under black light that intensified their psychadelic-ness. If you've been on a dark ride like Buzz Lightyear at Disneyland, you know the effect. The subject matter was aimed at horny teenage pot smoking boys: naked women, marijuana references, rock and roll, and comics. Some of the early Fillmore posters were beautifully designed, the later ones fall into the category of black velvet paintings of leopards. I can't decide if they are truly hideous or so hideous that they transcend into wonderful. I do know that if you find yourself in a friend's room filled with these you may be with the wrong crowd.